Wrapper cutting machine



March 18, 1958 T. JENSEN WRAPPER CUTTING MACHINE Filed Dec. 4, 1956United States Patent WRAPPER CUTTING MACHINE Thormod Jensen, New York,N. Y., assignor to Pollock Paper Corporation, Dallas, Tex., acorporation of Texas Application December 4, 1956, Serial No. 626,294

7 Claims. (Cl. 53-66) This invention relates to improvements in amachine for wrapping bread or other more or less irregular objects, .andrefers particularly to a mechanism for cutting a continuously fed webinto individual wrappers in timed relationship with the feeding ofobjects to be wrapped.

One of the important features of the present invention resides in awrapper cutter which is normally caused to function by a signal sent bya photoelectric cell but which, if excessively large or excessivelysmall objects are wrapped, is caused to operate mechanically.

Briefly described, the invention contemplates a wrapping machine whereina web of wrapping material is drawn forwardly by the article to bewrapped, the web carrying spaced substantially opaque dots whichnormally control a photoelectric cell, which in turn actuates a cutterknife for severing the web into individual wrappers, the device alsocontemplating a cam mechanism which may independently actuate the cutterknife when the article being wrapped draws greater or less thanpredetermined maximum or minimum lengths of wrappers.

Other objects, advantages and features of the present invention will beapparent from the accompanying drawing and followingdetaileddescription.

Referring in detail to the drawing, 1 indicates a roll of wrappingmaterial which in the case of wrapping bread, may be waxed paper,cellophane or the like. A web 2 may be drawn continuously from roll 1and may be passed around a guide roller 3; around a second guide roller4; around a floating roller 5 which functions as a web-tensioning means;around guide roller 6 and passed to the upper surface of table 7.

The web 2 carries a plurality of spaced substantially opaque signal dots8 which are spaced along the length of the web a distance from eachother'substantially equal to the length of the individual wrappers intowhich the web is to be severed, as will be hereinafter more fullydescribed. A control box 9 may be positioned adjacent table 7 and may beconnected by conductors 10 to a suitable source of electric power (notshown). .A light source 11 is connected to box S by conductors 12 and aphotoelectric cell 13 is connected to said box by conductors 14. Thetable 7 is provided with an aperture 15 whereby light from lightsource 11 may project therethrough, the dots 8 being adapted to travelover said aperture and periodically block the light normally transmittedto the photoelectric cell. The function of the photoelectric cell willbe hereinafter more fully described.

The general type of wrapping machine with which the present invention isparticularly usable is conventional and is shown and described in UnitedStates Patents 2,385,706, granted September 25, 1945, and 2,611,224,granted September 23, 1952, and is shown diagrammatically herein. Thepatents aforesaid are essentially bread wrapping machines and forpurposes of illustrating theoperation of the present invention, it willbe described in conjunction with use in wrapping loaves of bread.

In the operation of automatically wrapping bread, it is desirable thatthe advertising or design matter carried by each wrapper be disposedover the central upper portion of the loaf and in view of the fact thatthe loaves vary somewhat in girth, such variation is accommodated by theextent of the overlap. Hence, the present ma- Patented Mar. 18, 1958chine is so constructed that within the usual variation of girth of thebread, the wrapper advertising matter, etc. will be centrally locatedwith respect to the loaf and the variations will appear in the degree ofoverlapping of the wrapper ends.

In the conventional bread wrapping machine, loaves of bread 16 aredelivered continuously in seriatim by a suitable conveyor (not shown),which operates at substantially right-angles to the plane of thedrawing, to a delivery platform 17. A pusher 18, which operates in timedrelationship with a main cam shaft 19 of the machine, is disposedadjacent platform 17 and functions to move the loaf 16 in the directionof the arrow 20.

An end portion of the web 2, shown in broken lines at 21, is draped overa roller 22 carried by platform 7, the draped portion 21 disposesitself, as will be hereinafter more fully described, in the path oftravel of the leaf 16 when it isacted upon by the pusher 18.

A lifter table 23 is pivoted at one end, as at 24, said table beingswingable downwardly from the position shown in the drawing into planaralignment with platform 17. Hence, when pusher 18 moves the loaf 16 upontable 17, said loaf is moved to the lifter table and, in being so moved,partially enshrouds itself with the end portion 21 of web 2. The liftertable then moves to the position illustrated in the drawing, drawing theweb 2 over platform 7. Spaced bars 25, are also pivoted at 24, beingspaced at their opposite ends by a lap roller 26, the bars 25 straddlingthe lifter table 23.

The arrangement is such that bars 25 move downwardly as the lifter tablemoves upwardly to the position shown in the drawing and in doing so, thelap roller 26 engages the web causing the web to wrap about a portion ofthe loaf and further moving the web over platform 7. The lifter tableand bars 25 move in timed relationship with each other and with theother elements of the machine being also associated with main cam shaft19 by suitable conventional means (not shown).

A shear blade 27 is mounted upon a shear block 23 which is pivoted at 29for swingable movement. A shear plate 349 is carried upon the lowerportion of the lifter table 23 and cooperates with shear blade 27 inperforming a severing action upon web 2 when the shear block is rockedabout its pivot. The shear block 28 is biased by coil spring 31 formovement in a clockwise direction, as viewed in the drawing, and a link32 is pivotally connected to the shear block whereby said block may berocked in a counterclockwise direction against the tension of spring 31when the severing operation is performed.

As has been hereinbefore described, the present invention isparticularly directed to the cutting or severing of a web of wrappingmaterial into individual wrappers in timed relationship with the feedingof the objects to be wrapped. To accomplish this operation, a solenoid33 having a plunger 34 is positioned adjacent the lifter table 23, theplunger being pivotally connected to a link 35 which, in turn, ispivotally connectedto link 32. The solenoid is electrically connected tocontrol box 9 by conductors 36, interposed in one of which is a seriesswitch 37.

The arrangement is such that when an opaque dot 8 carried by web 2intercepts the light from light source 11 to photoelectric cell 13, asignal is sent to the control box which is relayed by conventional means(not shown) to solenoid 33, provided that switch 3'7 is closed, toactuate the solenoid. The actuation of the solenoid causes movement oflink 32 to move block 28 counterclockwise and effect the severing of theweb 2. Hence, under normal conditions, that is, when switch 37 isclosed, each time a dot 8 passes the aperture 15, the web is severedinto an individual wrapper.

A cam 38 is mounted upon cam shaft 19 and throughout an angle of about40its periphery has a reduced radius of curvature, as indicated at 39. Anactuating arm 40 is pivotally mounted,-as at 41, to the housing ofswitch 37 and at the opposite end, the arm 40 carries a follower roller42 which rides upon the periphery of cam 38. Switch 37 is of t henormally closed type and comprises a resiliently biased control pin 43which bears upon arm 40 and causes roller 42 to bear upon the peripheryof cam 38. r

The arrangement is such that during the major portion of a revolution ofcam shaft 19 the switch 37 is held by arm 4 in open position, butwhenroller 42 encounters the indented portion 39 of the cam periphery, thespringpresscd pin protrudesoutwardly and the switch 37 returns to itsnormally closed position. At this phase sole noid 33 is placed incircuit with the control box Q and when the signal dot 8 passes thelight source-photoelectric cell assembly, theisolenoid will be actuated.However, it. can be, seen that if the dot 8 passes. the light sourcephotoelectric assembly when the follower roller 42 is riding on theportion of the cam periphery of large radius of curvature, the solenoidwill not be actuated since switch 37 will beopen. v I

The cam 38 is also provided, in its face, with a cam groove 44 definedby an inner wall 45 and an outer wall Throughout a major portion of arevolution of cam 35, the walls 45 and 46 are substantially circular andconcentric. However, for an angle of about the outer wall extendsradially outwardly, as shown at 47 and in substantial alignment with theinitial 40 radial line 48, considered in the direction of rotation ofthe cam, the inner wall bulges outwardly, as shown at 49.

It will be noted that the angular span of the depressed portion 39 issubstantially diametrically opposite the angular span of the portion 47and that the bulge 49 is disposed l80 away from the trailing end of thedepressed portion 39, considered in the direction of rotation of thecam. The purpose of this arrangement will be hereinafter more fullydescribed.

A lever 50 is pivoted at one end, as at 51, to a portion of the machineframe. The opposite end of lever 50 is pivotally connected, as at 52, tothe pivotal juncture of links 32 and 35. A cam follower roller 53 ismounted intermediate the length of lever 50 and bears upon the innerwall 45 of the cam groove 44 under the influence of spring 31.

Thus, link 32 may be moved to actuate cutter block 28 by two means,solenoid 33 or lever 50 when cam roller 53 engages the bulge 49. It willbe noted that the cutter blade 27. can only be actuated when the camroller 53 rides upon that portion of the inner wall spanned by theradial lines .48 and 54 since the outer wall only recedes radiallyoutwardly at the aforesaid span. In addition, the solenoid 33 can onlyfunction to move the cutter blade during this angular span since saidspan also controls the period of close of switch 37.

In the operation of the device, the device is initially set for apredetermined average girth of the article to be wrapped, for instance,for a loaf of bread of average girth. Of course, it is substantiallyimpossible to control absolutely the girth of each succeeding loaf ofbread fed to the machine and. variations are bound to occur. However,the solenoid 33 without being restrained by cam 38 can accommodate thesechanges in girth through an angle of about 40- which represents, withinsaid 40 tolerance a predetermined variation of overlap of the wrappersupon thebreadr However, it may so happen that a loaf of unusually smallgirth may be fed to the machine. In view of the fact that the initialwrap of the bread determines the extent that the web 2 is drawn overtable 7, it may so happen that the web is drawn to positions. signal dot8 just short of the aperture 15. Hence, for this loaf of bread nosignaltwill be sent to the control box 9 and solenoid 33 will not becaused to operate. t However, when the. end of the actuating 40 on thetable 7 that when pusher 18 next operates, a dot 8 will immediately passthe aperture. A cutting'signal will then be sent to box 9, but at thisperiod of dperation, roller 42 is no longer on the depressed portion 39of the cam periphery and, hence, switch 37 will beopen. Accordingly, thecutting signal will not be transmitted to solenoid 33 and the cutterwill remain inactive until the next signal dot 8 is reached, if thisoccurs during the actuating 40 angle span of the cam. If nosignal is isent to the solenoid during the actuating 40 angle, the

bulge 49 will again operate the cutter.

Of course, in normal operation, inasmuch as the aver- Y age girth of theloaves may be controlled, an unusually t small loaf will be followed bya larger loaf and the function of the cutting operation will thenreturnto the solenoid 33.

The machine also compensates for unusually large loaves, in which case,two signal dots may be pulled past the aperture 15 by one loaf. In thiscase, the closing period of switch 37 will not be reached when thesecond signal is given and solenoid 33 will not be energized;

However, the bulge will again perform the cutting operation.

If a series of unusually small or unusually large loaves of bread areencountered, it means that the average size loaf 1s mlsconceived andwrappers having smaller or greater spacing between dots 8 should beused.

It is to be understood, of course, that the actuating angle of 40 is notcriticalper se and-said angle may be larger or smaller, as desired.However, for the wrapping of bread an angle of about 40 is preferred.

Other unpatentable modifications which do notde'part from the essence ofthe invention may be made by those skilled in the art and, hence, it isnot intended that the invention be limited to the exact details shownand described except as necessitated by the appendedclaims.

I claim as my invention:

1. A wrapper cutting device which comprises, means for, supporting aforwardly moving web of wrapper material having a plurality ofsubstantially opaque signal dots spaced lengthwise upon said web,electric signalproducing means disposed adjacent said support'to producean electric signal when a dot passes adjacent said signal-producingmeans, means for draping an end por tion of said web around an articleto be wrapped; means for moving said article laterally to envelope thearticle with the web and move the web over said support a distancesubstantially proportional to the lateral girth of said article, acutter for cutting the web between theweb support and said movedarticle, electrical means for actuating said cutter, connecting meansbetween said electrical means and signal-producing means for actuatingsaid electrical means in response to said signal, a cam movable in timedrelationship to the movement of said article-moving means, electricswitch means connected in said connecting means for connecting anddisconnecting said electrical actuating means and said signal-producingmeans, a cam follower controlled by said cam for closing said switchmeans for a predetermined angular movement of said cam, a second cammovable in timed relationsip to said first-mentioned cam, a secondfollower means controlled by said second cam, means connecting saidsecond follower means to said cutter to actuate said cutter atsubstantially the period at which the switch means opens.

,2. A wrapper cutting device which comprises, means for supporting aforwardly fed web of wrapper material I having a plurality ofsubstantially opaque signal dots asaassa spaced lengthwise upon saidweb, a light source-photoelectric cell assembly disposed adjacent saidsupport to produce an electric signal when a dot carried by said webpasses between said light source and photoelectric cell, means fordraping an end portion of said web around an article to be wrapped,means for moving said article laterally to envelope the article with theweb and move the web over said support a distance proportional to thelateral girth of said article, a cutter for cutting the web between theweb support and said moved article, electrical means for actuating saidcutter in response to said signal, a cam movable in timed relationshipto the movement of said article-moving means, electric switch meanscontrolling the connection between said electrical actuating means andsaid light source-photoelectric cell as sembly, a cam followercontrolled by said cam for closing said switch means for a predeterminedangular movement of said cam and opening it for the remainder of theangular movement of the cam, a second cam movable in timed relationshipto said first-mentioned cam, a second follower means controlled by saidsecond cam, means connecting said second follower means to said cutterto actuate said cutter at substantially the period at which the switchmeans opens.

3. A wrapper cutting device which comprises means for supporting aforwardly moving web of wrapper material having a plurality of signaldots spaced lengthwise upon said web, electric signal-producing meansdisposed adjacent said support to produce an electric signal when a dotpasses adjacent said signal-producing means, means for moving thearticle to be wrapped into contact with an end portion of said weblaterally to envelope the article with the web and move the web oversaid support a distance substantially proportional to the girth of saidarticle, a cutter for cutting the web between the support and said movedarticle, electrical means connected to said signal-producing means foractuating said cutter in response to said signal, a cam movable in timedrelationship to the movement of said article-moving means, normallyclosed electric switch means connected between said signal-producingmeans and actuating means for connecting and disconnecting saidelectrical actuating means from said signal-producing means, a camfollower controlled by said cam for permitting said switch to close onlyfor a predetermined angular movement of said cam, a second cam movablein timed relationship to said firstmentioned cam, a second followermeans controlled by said second cam, means connecting said secondfollower means to said cutter to actuate said cutter at substantiallythe period at which the switch means opens after its period of close.

4. In a machine for wrapping sequentially fed articles of varying girthswherein the wrapping of the article draws a web of wrapping material ofa length proportional to the girth of the article from a support of saidweb material, and wherein said web material carries longitudinallyspaced signal triggering dots, the combination with said machine of aweb cutting device for severing the Web into individual wrappers forsaid articles, said web cutting device comprising, a cutting knife, asignalproducing means disposed adjacent said web for transmitting anelectrical signal in response to the passage of a signal triggering dot,electrical means connected to said signal transmitting device foractuating said cutting knife in response to a received signal, anelectric switch connected between said signal transmitting device andsaid electrical cutting knife actuating means, a cam movable in timedrelationship to the passage of said web to open and close said switch, acam follower controlled by said cam opening said switch for only apredetermined angular travel of said cam, a second cam movable in timedrelationship with said first-mentioned cam, second cam follower meanscontrolled by said second cam for actuating said cutting knife atsubstantially the time when said switch means is opened.

5. In a machine for wrapping sequentially fed articles of varying girthswherein the wrapping of the article draws a web of wrapping material ofa length proportional to the girth of the article from a supply of saidweb material, and wherein said web material carries longitudinallyspaced signal triggering dots, the combination with said machine of aweb cutting device for severing the web into individual wrappers forsaid articles, said web cutting device comprising, a cutting knife, asignalproducing means disposed adjacent said web for transmitting anelectrical signal in response to the passage of a signal triggering dot,electrical means connected to said signal transmitting device foractuating said cutting knife in response to a received signal, a cammovable in timed relationship with the passage of said web, cam followermeans controlled by said cam, means for connecting said cam followermeans and said cutting knife for actuating said cutting knife at apredetermined phase of revolution of said cam, said cam follower beingrestrained from movement by said cam for a major portion of therevolution of the cam and being unrestrained by said cam for a minorportion of the revolution of the cam.

6. In a machine for wrapping sequentially fed articles of varying girthswherein the wrapping of the article draws a web of wrapping material ofa length proportional to the girth of the article from a supply of saidweb material, and wherein said web material carries longitudinallyspaced signal triggering dots, the combination with said machine of aweb cutting device for severing the web into individual wrappers forsaid articles, said web cutting device comprising, a cutting knife, asignal-producing means disposed adjacent said web for transmitting anelectrical signal in response to the passage of a signal triggering dot,electrical means connected to said signal transmitting device foractuating said cutting knife in response to a received signal, anelectric switch connected between said signal transmitting device andsaid electrical cutting knife actuating means, a cam movable in timedrelationship to the passage of said Web, a cam follower controlled bysaid cam closing said switch for only a predetermined angular travel ofsaid cam.

7. In a machine for wrapping sequentially fed articles of varying girthswherein the wrapping of the article draws a web of wrapping material ofa length proportional to the girth of the article from a supply of saidweb material, and wherein said web material carries longitudinallyspaced signal triggering dots, the combination with said machine of aweb cutting device for severing the web into individual wrappers forsaid articles, said web cutting device comprising, a cutting knife, asignal-producing means disposed adjacent said web for transmitting anelectrical signal in response to the passage of a signal triggering dot,electrical means connected to said signal transmitting device foractuating said cutting knife in response to a received signal, anormally closed electric switch connected between said signaltransmitting device and said electrical cutting knife actuating means, acam movable in timed relationship to the passage of said web, a camfollower controlled by said cam opening said switch for only apredetermined angular travel of said cam, a second cam movable in timedrelationship with said first-mentioned cam, second cam follower meanscontrolled by said second cam, means for connecting said second camfollower means to said cutting knife for actuating said cutting knife atthe beginning of said predetermined travel of the first-mentioned cam,said second cam follower means being restrained from movement by saidsecond cam throughout said predetermined angular travel of said firstcam and being unrestrained by said second cam during the remainingangular travel of said first cam.

No references cited,

